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Multichannel pseudogap Kondo model: Large-N solution and quantum-critical dynamics

Matthias Vojta
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Abstract

We discuss a multichannel SU(N) Kondo model which displays non-trivial zero-temperature phase transitions due to a conduction electron density of states vanishing with a power law at the Fermi level. In a particular large-N limit, the system is described by coupled integral equations corresponding to a dynamic saddle point. We exactly determine the universal low-energy behavior of spectral densities at the scale-invariant fixed points, obtain anomalous exponents, and compute scaling functions describing the crossover near the quantum-critical points. We argue that our findings are relevant to recent experiments on impurity-doped d-wave superconductors.

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Matthias Vojta. 2001-08-07. Multichannel pseudogap Kondo model: Large-N solution and quantum-critical dynamics. https://doi.org/10.1103/physrevlett.87.097202

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